The purpose of this project is to define the genome structure of the non-defective parvovirus, Aleutian disease virus (ADV). A double stranded intracellular form of ADV DNA analogous to replicative form DNA of other parvovirus has been isolated. This DNA has been mapped with restriction endonucleases. The restriction map differs completely from those reported for other parvoviruses. Three segments of the DNA have been molecularly cloned (0.05-0.15 map units, 0.15-0.56 map units) in bacterial systems. Plans are to clone the remaining DNA segments, and use these reagents to compare DNA from various isolates of ADV that differ in their virulence for mink.